Lowrance hds7 nmea connections

[alisdair4]

I am very concious that " the only stupid question is the one you don't ask". Sometimes, i feel I am stretching this to the limit! I am currently trying to make my new Lowrance HDS7 output GPS info to a laptop running Seapro,and take in AIS data from a NASA AIS.

The connections which i am trying to make work are currently as follows:

AIS: Black to Lowrance Blue ( serial pin 3).
AIS: screen to Lowrance Yellow(ground, pin 5)

Plotter: serial brown( pin 2) to Lowrance Green.
Plotter: serial red (pin 3) to Lowrance Blue.
Plotter: serial yellow ( pin 5, ground) to Lowrance Shield.
Plotter: serial blue (pin 7) to Lowrance Yellow.
Plotter: serial violet (pin8) to lowrance Orange.

The serial cable is a DB9.

Despite me thinking I had rrsearched this sufficiently in advance, I see no GPS info on the laptop, and no AIS info on the plotter!

Any ideas?

 

[pvb]

Have you configured the AIS input and GPS output in the Network Menu?

 

[Shanty]

Shanty has a Lowrance HDS10 plotter. However, I've set it up on a NMEA 2000 network. I think Seapro, and possibly NASA AIS use NMEA 0183, so you will have some fiddling about to do.

From memory, I think there are two versions of NMEA 0183. Both ends must be using the same version.

NMEA 0183 supports a range of baud rates. Again, both ends must use the same rate.

NMEA 0183 requires a talker and a listener on each link (can't remember how you set this up)

The Lowrance has a settings screen that lets you define which data sentences will be sent or recognised - the default will probably have all you need, but check.

Anyway, good luck. You will have to do a bit of trial and error before you get all three devices communicating. NMEA 2000 is much, much easier.

 

[nigelmercier]

Any ideas?

It would probably be easier to diagnose if you said what the function of the wires were, rather than the colours.

 

[alisdair4]

Thanks Nigel!

That comment actually made me look afresh at the problem, and I solved it in about an hour this morning - so thank you.

For future reference, the solution is pretty straightforward.

The Lowrance is set to COM 1 (RS422), the only option available on NMEA 0183 on this model. Baud rate is 38400.

NASA AIS wiring is: Black wire to Lowrance Orange wire (RX+). Ground wire to Lowrance Shield.

Wiring to take the GPS signal to the laptop using a DB9 Serial/USB adapter is:

Lowrance Yellow (TX+) to Serial Pin 2 ( Receive data).
Lowrance Shield to Serial Pin 5 (Ground).

FWIW, I am highly impressed by the plotter - it is clear even in the bright sunshine we had this morning, and the AIS function is quick and simple to use. Most important, it is there in the cockpit, not down at the nav station.

I won't mention choc block connectors....!